Fall SAVY 2016 (Day 2) – Intro to Macromolecules

Posted by hallep on Monday, October 3, 2016 in Grade 3, Grade 4, SAVY.

This week in Introduction to Macromolecules, we built on (quite literally, in fact, using our gumdrop and toothpick molecular models) the material we learned last week about atomic structure and bonding to create functional groups. Functional groups are groups of atoms bonded together in a certain way that give molecules characteristic properties. Based on our previous knowledge of how many bonds certain types of atoms typically form, the students were challenged to build various functional groups. We then built the monomers that, when bonded together, form polymeric macromolecules. Each group constructed a different type of monomer—an amino acid, a fatty acid, or a glucose molecule—noting which type(s) of functional group each contained. I then briefly introduced how these monomers are the building blocks of the macromolecules proteins, lipids (fats), and carbohydrates, respectively; we will cover each of these classes of macromolecules in much greater depth, one per class period, beginning next week with carbohydrates.

During the latter part of the morning, we focused our attention on understanding how carbohydrates, lipids, and proteins provide us with energy. We learned that our bodies must exert some energy to digest food, but that during the process a greater amount of energy is released that the body harnesses to carry out its functions. The amount of energy a food provides is reflected in the number of calories listed on the product’s nutrition facts label. Carbohydrates and proteins provide us with 4 calories/gram, while fats provide us with 9 calories/gram. The students used this newly acquired knowledge to assess the nutritional content of various foods, performing mathematical calculations to determine the number of calories from each type of macromolecule and the percentage of total calories in the food product from each type. Some of the students elected to take home these worksheets; if they did, I encourage you to allow them to continue this exercise at home with their own favorite snacks.

I also encourage you to discuss the following “food for thought” questions with your child (also listed at the bottom of the described worksheet):

• If a certain food has a lot of calories, why do most people consider that bad?
• If two food products have the same number of calories, why are some considered “healthy” and others “unhealthy”?
• If you were on a deserted island and could have a certain mass of only one type of macromolecule, which would you choose and why?

I’m looking forward to seeing everyone next week as we dive into the sweet (pun intended) world of carbohydrates!

–Michelle